Flash Flood in Kansas, July 30, 2007

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
629 AM CDT MON JUL 30 2007

.DISCUSSION...

310 AM CDT MON...
CONTINUED MESSY UPPER AIR PATTERN OVER THE CNTRL CONUS WITH CUTOFF
LOW PRESSURE RETROGRADING SW OVER SERN NM...AND RIDGE AXIS EXTENDING
FROM THE CNTRL ROCKIES THROUGH THE NRN PLAINS. IN BETWEEN...SEVERAL
WEAKLY DEFINED CONVECTIVELY ENHANCED VORTICITY CENTERS MEANDER
RATHER AIMLESSLY FROM CNTRL NEBRASKA THROUGH SWRN MISSOURI. IN THE
LOW LEVELS...PERSISTENT BOUNDARY REMAINS STRUNG FROM SRN MISSOURI
THROUGH ERN COLORADO...AND HAS BEEN THE FOCUS FOR POOLING MOISTURE
AND ENHANCED LIFT. BOTH IR AND FOG CHANNEL SATELLITE IMAGERY
INDICATES A SOMEWHAT DRIER AIRMASS MAKING MINOR INROADS ACROSS THE
NRN QUARTER OF MISSOURI.

BOUNDARY ACROSS CNTRL KANSAS SHOULD CONTINUE TO PERCOLATE WITH
DEEPER CONVECTION AS 20-30KT LLJ FEEDS RICHER MOISTURE NWD. MODELS
ALSO INDICATE RATHER ROBUST ISENTROPIC LIFT IN THE 305K-310K LAYER
THROUGH THE MORNING HOURS. MODEL ISENTROPIC ANALYSIS INDICATES LIFT
PROGRESSING FURTHER NORTH OF BOUNDARY WITH TIME...AND THIS TREND
APPEARS REFLECTED WELL IN BOTH THE GFS AND NAM-WRF QPF FIELDS.
BIGGEST QUESTION IS HOW FAR EAST CAN THIS PRECIPITATION FIELD
SURVIVE...AND HOW MUCH ADDITIONAL CONVECTIVE DEVELOPMENT WILL OCCUR
WITH HEATING THIS AFTERNOON. AGAIN TONIGHT...GFS SEEMS TO HAVE THE
BEST HANDLE ON THE SITUATION...AND WILL FOLLOWS ITS LEAD ALONG WITH
PERSISTENCE TRENDS OF GREATEST PRECIP CHANCES REACHING/DEVELOPING
ALONG THE STATE LINE. HOWEVER...GIVEN A VIRTUALLY UNCAPPED
ATMOSPHERIC PROFILE AND THICK MOISTURE BACKING WEST INTO THE
BOUNDARY...CANNOT TOTALLY RULE OUT A THUNDERSTORM JUST ABOUT
ANYWHERE WEST OF US-65 THIS AFTERNOON.

MODELS SEEM TO TREND TOWARDS A DRIER FORECAST PAST THIS EVENING AS
DEEPER ELY FLOW DEVELOPS OVER MOST OF THE AREA...AND LOW LEVEL
BOUNDARY BECOMES WASHED OUT AS LEE TROUGHING TO THE WEST MIXES FROM
ALOFT. HOWEVER...GIVEN THE CHAOTIC PATTERN ALOFT...NOT CONFIDENT IN
PORTRAYING A TOTALLY DRY FORECAST...ESPECIALLY FOR POINTS IN THE FAR
SWRN CWA. HAVE TRENDED DRIER AND WARMER BY MIDWEEK ALONG THE LINES
OF THE GFS DEPICTION.

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&&

.AVIATION...

VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD AT ALL TERMINALS.
BULK OF THE SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TO STAY
JUST TO THE SOUTHWEST OF THE KANSAS CITY METRO AREA AS THE WEAK
SFC-850MB BOUNDARY REMAINS ANCHORED. HOWEVER HIT AND MISS TYPE
SHOWERS AND ISOLATED THUNDERSTORMS COULD FORM JUST ABOUT ANYWHERE UP
AND DOWN THE MO/KS STATE LINE THIS AFTERNOON...AS THE AIRMASS
BECOMES MORE TROPICAL.

NRR

&&

.EAX WATCHES/WARNINGS/ADVISORIES...

MO...NONE.
KS...NONE.

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
548 AM CDT MON JUL 30 2007

KSZ025-057-060-102>105-MOZ001>008-011>017-020>025-028>033-037>040-
043>046-053-054-311100-
ATCHISON KS-MIAMI-LINN KS-DONIPHAN-LEAVENWORTH-WYANDOTTE-
JOHNSON KS-ATCHISON MO-NODAWAY-WORTH-GENTRY-HARRISON-MERCER-
PUTNAM-SCHUYLER-HOLT-ANDREW-DE KALB-DAVIESS-GRUNDY-SULLIVAN-ADAIR-
BUCHANAN-CLINTON-CALDWELL-LIVINGSTON-LINN MO-MACON-PLATTE-CLAY-
RAY-CARROLL-CHARITON-RANDOLPH-JACKSON-LAFAYETTE-SALINE-HOWARD-
CASS-JOHNSON MO-PETTIS-COOPER-BATES-HENRY-
548 AM CDT MON JUL 30 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWEST...NORTH CENTRAL
AND WEST CENTRAL MISSOURI...AS WELL AS EXTREME EASTERN KANSAS.

.DAY ONE...TODAY AND TONIGHT

AN AREA OF HEAVIER SHOWERS AND ISOLATED THUNDERSTORMS WAS MOVING
THROUGH EAST CENTRAL KANSAS AND WEST CENTRAL MISSOURI...GENERALLY
ALONG AND SOUTH OF A LINE FROM ADRIAN TO PAOLA. LOCALLY HEAVY
RAINFALL IS POSSIBLE WITHIN THIS AREA...THOUGH WIDESPREAD FLOODING
IS NOT EXPECTED.

ADDITIONAL THUNDERSTORM DEVELOPMENT IS POSSIBLE AGAIN THIS
AFTERNOON...GENERALLY SOUTH AND WEST OF A LINE FROM CLINTON TO
KANSAS CITY TO ROCKPORT. THESE STORMS ARE NOT EXPECTED TO BE SEVERE.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOR ANTICIPATED.

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